PAM4 equalization DSM

1. A method of automatically equalizing a PAM4 signal, comprising: generating a reference signal for the PAM4 signal by slicing the PAM4 signal into a first level and a second level; determining a constant coefficient; amplifying the reference signal by the constant coefficient, wherein the amplified reference signal is used to modulate the PAM4 signal; determining a first signal amplitude measurement of the PAM4 signal; determining a first signal boost measurement of the PAM4 signal; determining whether the first signal boost measurement and the signal amplitude measurement are substantially consistent with each other; responsive to determining that the signal boost and the signal amplitude are not substantially consistent with each other, determining a reference amplification modification; and calibrating a PAM4 signal according to the determined reference amplification modification.

2. The method of claim 1 , further comprising; responsive to determining that the first signal boost measurement and the first signal amplitude measurement are substantially consistent with each other, initiating a sleep period using a sleep timer; determining whether the sleep period has elapsed; and responsive to determining that the sleep period has elapsed, determining a second signal amplitude measurement of the PAM4 signal; and determining a second signal boost measurement of the PAM4 signal.

3. The method of claim 1 , further comprising, responsive to determining that the sleep period has not elapsed, initiating a second sleep period.

4. A system for equalizing a PAM4 signal, comprising; an PAM4 signal equalizer configured to: generate a reference signal for the PAM4 signal by slicing the PAM4 signal into a first level and a second level; determine a constant coefficient; amplify the reference signal by the constant coefficient, wherein the amplified reference signal is used to modulate the PAM4 signal; determine a first signal amplitude measurement of the PAM4 signal; determine a first signal boost measurement of the PAM4 signal; determine whether the first signal boost measurement and the signal amplitude measurement are substantially consistent with each other; and responsive to determining that the signal boost and the signal amplitude are not substantially consistent with each other, determine a reference amplification modification; and calibrate a PAM4 signal according to the determined reference amplification modification.

5. The system of claim 4 , wherein the PAM4 signal equalizer is further configured to; responsive to determining that the first signal boost measurement and the first signal amplitude measurement are substantially consistent with each other, initiate a sleep period using a sleep timer; determine whether the sleep period has elapsed; and responsive to determining that the sleep period has elapsed, determine a second signal amplitude measurement of the PAM4 signal; and determine a second signal boost measurement of the PAM4 signal.

6. The system of claim 4 , wherein the PAM4 signal equalizer is further configured to, responsive to determining that the sleep period has not elapsed, initiate a second sleep period.